Lockable receiver for pneumatic tube conveying systems



Dec. 24, 1968 w. R. STIEBER 3,417,941

LOCKABLE RECEIVER FOR PNEUMATIC TUBE CONVEYING SYSTEMS Filed April 18,1967 2 Sheets-Sheet l /fl l5 ATTORNEYS.

1968 w. R. SITIEBER 3,417,941

LOCKABLE RECEIVER FOR PNEUMATIC TUBE CONVEYING SYSTEMS Filed April 18,1967 2 Sheets-Sheet 2 '[l/l/[l/l/ll/lll ll III/11111111] 1111/11l/I/l/Il/ll/ 1/! United States Patent Office 3,417,941 Patented Dec. 24,1968 3,417,941 LOCKABLE RECEIVER FOR PNEUMATIC TUBE CONVEYING SYSTEMSWolfgang R. Stieber, River Vale, N.J., assignor, by mesne assignments,to The Mosler Safe Company, a corporation of New York Filed Apr. 18,1967, Ser. No. 631,812 12 Claims. (Cl. 24316) ABSTRACT OF THE DISCLOSUREA pneumatic tube conveying system is disclosed having receiver deviceswhich are provided with electromagnetically operated locks for lockingthe receiver devices and thereby preventing unauthorized removal of thecarrier upon arrival at the receiver. The electromagnetic locks areselectively actuated to lock the receiver in response to a commandsignal generated by the one initiating the carrier transmission and aredeenergizable for unlocking the receiver in response to a key operatedswitch located at the receiving station for which only authorizedpersonnel are provided keys.

This invention relates to pneumatic tube conveying systems and moreparticularly to pneumatic tube conveying systems having receivingstations which can be locked to prevent unauthorized removal oftransmitted carriers.

Pneumatic tube conveying systems of the type in which this inventionfinds particular utility generally include pneumatic tube linesinterconnecting a plurality of widely scattered stations. Messages,securities, small articles and the like, are transported from onestation to the other in carriers which are propelled through the tubesby pneumatic pressure. In installations of this type, the sender directsthe carrier to a selected station in one of a number of ways. Forexample, the sender may dial the number of the selected station on atelephone-type dial located at the central station and forming part of acentral control system. Alternatively, the sender may set the number ofthe selected station on the carrier itself by manipulatingdials on thecarrier, these dials being effective to vary the interconnection betweena plurality of conductive rings, or the like, mounted on the carrierbody.

In either case, after the carrier has been inserted into the pneumaticline it is automatically directed to the receiving station by means ofvarious conventional, electrically controlled devices such as a centraltransfer unit, station deflectors and the like. After the carrierarrives at the selected station, it is stored in a receiver unit untilit is removed.

Frequently in the use of these penumatic tube systems it is desirable toprevent unauthorized personnel from having access to the receiverdevice. Such is the case, for example, in systems installed in hospitalsWhere carriers containing narcotics are frequently transported throughthe systems for distribution to different receiving stations. To providefor such restricted access transmissions, it has been proposed in thepast to permanently lock the receiver devices and provide onlyauthorized personnel with keys for unlocking them. In this manner, onlythose authorized personnel having keys can gain entrance to the receiverdevices for withdrawing the secured, or classified, carrier.

One very serious disadvantage of the prior art, permanently lockedreceiver proposal is that the receiver device is not available forreceipt of unsecured, or unclassified, carrier transmissions. To makeprovisions for such unsecured transmissions, it has been necessary toprovide a second pneumatic tube system having receiver devices which arenot key-locked. The obvious difliculty with such a solution is that itinvolves costly and unnecessary duplication.

It has been a principal object of the present invention to provide animproved pneumatic tube conveying system for handling both secured andunsecured carrier transmissions. In the present system one or morereceiving stations are provided with electrically locked doors. Thesender, at the same time that he is establishing the signals to direct acarrier, establishes another signal to lock the receiver if desired.Thus, the receiving station need be provided with only a single receiverdevice and the sender can control whether this receiver device is placedin a locked or unlocked condition when a carrier arrives. Thus, in onepreferred embodiment, the receiver device remains unlocked, permittingunsecured transmissions unless or until a lock command is generated bythe one initiating the transmission, whereupon the receiver devicebecomes locked and remains so until opened by authorized personnel atthe receiving station.

It has been a further principal objective of this invention to provide apneumatic tube conveying system having dual purpose receiver devicesoperable in both a secured and unsecured mode which are simple andreliable in construction and operation.

The above objective is achieved in accordance with the principles ofthis invention by utilizing a novel and unobvious approach in which thereceiver devices are provided with electromagnetically operated lockswhich are energizable for locking the receiver device in response to acommand generated by the one initiating the carrier transmission, andde-energible for unlocking the receiver in response to a key-operatedswitch located at the receiving station for which only authorizedpersonnel are provided keys.

In one preferred embodiment of this invention the command is in the formof a lock switch located at the transmitting station. This switch, whenactuated by depressing a button or the like, completes a self-latchingcircuit for energizing the electromagnetic receiver lock. The circuitonce latched remains latched, locking the receiver until thekey-operated switch is actuated, whereupon the latching circuit isinterrupted and the electromagnetic lock deenergized, permitting accessto the receiver device for withdrawal of the carrier.

In a second preferred embodiment of this invention, the command foroperating the electromagnetic receiver lock is obtained by providing thecarrier with a detectable security designation indicator which is sensedby a reader associated with the pneumatic tube as the carrier passesthrough the tube toward the receiving station. The reader, in responseto sensing the security designation indicator, completes a latchingcircuit for energizing the electromagentic receiver lock. This circuit,like the latching circut of the other preferred embodiment, remainslatched locking the receiver, until the key is inserted into the switchat the receiving station, unlatching the energization circuit for thelock and thereby permitting access to the receiver for carrier removal.

The various features and advantages of the invention will be moreclearly apparent to those skilled in the art from the followingdescription taken in conjunction with the drawings:

FIGURE 1 is a schematic diagram of one preferred embodiment of a portionof pneumatic tube conveying system having a lockable receiverconstructed in accordance with the principles of this invention.

FIGURE 2 is a schematic diagram of a portion of a second preferredembodiment of a pneumatic tube conveying system having a lockablereceiver constructed in accordance with the principles of thisinvention.

FIGURE 3 is a schematic perspective view of a carrier suitable for usewith the embodiment of FIGURE 2, and

FIGURE 4 is an elevational view in cross-section of a receiver, showingthe details of the electromagnetic receiver lock.

One section of a preferred embodiment of a pneumatic carrier conveyingsystem constructed in accordance with the principles of this inventionis depicted in FIGURE 1. This embodiment includes a transmitting station10, receiving station 11 and a control circuit 12 appropriatelyconnecting the transmitting station and the receiving station. As thoseskilled in the art will appreciate, the pneumatic tube system mayinclude a plurality of transmitting stations and a plurality ofreceiving stations located at different points throughout the system forservicing different locations.

The system of FIGURE 1 has two principal modes of operation, namely, aconventional or nonsecurity mode and a security mode. In theconventional mode a carrier C is inserted into a main pneumatic tube 16through a tube insertion port 13 at the transmitting station and theappropriate destination switch 14 depressed corresponding to thedestination to which it is desired to send the carrier. Actuation of thedestination switch 14 functions to operate a station deflector 15 as thedesired receiving station 11, which deflects the transmitted carrierfrom the main pneumatic tube 16 to a receiver 17 located at thereceiving station. Upon arrival of the carrier at the receiver 17, thecarrier is free to be removed by an attendant for processing as desired.The deflector 15 is automatically reset, conditioning the system forfurther carrier transmissions, by means to be described.

In the other mode of operation, the security mode, the carrier C isinserted into the main pneumatic tube 16 through the tube insertion port13. As in the conventional mode of operation, a destination switch 14corresponding to the destination to which the carrier is to betransmitted is depressed. Actuation of the destination switch 14operates, as described above, to actuate the station deflector 15 fordeflecting the carrier to the receiver 17 upon arrival at the receivingstation 11. In addition and unlike in the conventional mode ofoperation, a security button 20 is also depressed. Depression of thesecurity button, which is also located at the transmitting station,functions, through the control circuit 12, to actuate an electromagneticreceiver lock 22. The electromagnetic receiver lock 22 upon actuatingprevents withdrawal of the carrier from the receiver 17 except byauthorized personnel possessing a security key designed to de-actuatethe electromagnetic lock and permit access to the receiver.

The transmitting station, more specifically, includes the tube insertionport 13 through which the carriers C are inserted into the mainpneumatic tube 16. The tube insertion port 18 may be of any of thewell-known designs and consequently is not described in detail. Thetransmitting station also includes the destination switch 14 which has anormally open movable contact 25 connected between a destination relay27 via line 28 and a grounded terminal 26. The destination switch 14initiates operation of the deflector associated with the receivingstation to which transmission is desired. The transmitting station 10further includes the security switch having a normally open movablecontact 29 which is connected between a grounded terminal 30 and anormally open conditioning contact 31 of the control circuit 12. Thesecurity switch 20 functions when actuated to operate theelectromagnetic locking means 22 at the receiver 17 for preventingunauthorized removal of carriers. Also forming part of the transmittingstation 10 is a security lamp 35 connected between a source of positivepotential 36 and a normally open security lamp contact 37 of the controlcircuit 12. The other side of the lamp contact 37 is connected to ground34. The lamp provides a visual indication to transmitting stationpersonnel when the locking means 22 is actuated.

Should there be plural receiving stations 11 in the system, thedestination switches 20 and security switches 14 will equal in numberthe number of receiving stations, and be adapted to actuate thedeflectors 15 and receiver locks 22 associated with their respectivereceiving stations.

The receiving station 11 includes the station deflector 15 which is alsoof conventional and well-known design and, therefore, is not describedin detail. The deflector 15 includes a deflector solenoid 38 connectedbetween a source of positive potential 39 and a grounded terminal 40 viaa normally open station deflector contact 41 of the control circuit 12.The deflector solenoid 38 is mechanically linked to the deflectormechanism (not shown) of the station deflector 15 and when energizedfunctions to intercept a transmitted carrier traveling in the mainpneumatic tube 16 and deflect it into the receiver 17 via a station tube18.

The receiver 17, as shown in FIGURE 4, is a modified form of theconventional receivers well-known in the art. The modification involvesthe addition to the conventional receivers of a electromagnetic receiverlock 22. The lock 22 may, for example, include an electromagnet 70 whichis mechanically coupled to a conventional latching device 71 on thereceiver closure 73. The latching device 71 preferably includes ahorizontal latch pin 75 shiftable in supports 74A and 74B secured to theclosure 73 between a rightward lock position wherein the pin end 76engages a hole 77 in the receiver wall 78 locking the closure, and aleftward unlock position wherein the pin end and hole are disengaged,unlocking the closure. A bias spring 79, which urges the latch pinleftwardly, is used to keep the receiver closure 73 unlocked when theelectromagnet 70 is not energized, permitting free access to thereceiver. The electromagnet 70 overcomes this spring bias whenenergized, preventing access to and removal of a carrier from thereceiver 17 except by authorized personnel possessing the security key(FIGURES 1 and 2) designed to permit de-energization of theelectromagnetic lock 22 and access to the receiver 17.

The electromagnetic receiver lock 22 is connected between a source ofpositive potential 45 and a grounded terminal 46 via a receiver lockcontact 47 of the control circuit 12. As indicated previously, theelectromagnetic receiver lock 22 may be of any desired constructionwhich functions to lock the receiver closure when the electromagnet isenergized and unlock the receiver door when the electromagnet isde-energized. Alternatively, by altering the spring biasing of thelatching device and the normal state of energization of theelectromagnetic lock 22, the lock may function to lock the receiver whende-energized and unlock it when energized.

The receiving station 11 also includes a deflector reset contact 50which is connected between a grounded terminal 51 and a latching contact52 of the control circuit 12. The deflector reset contact 50 functionsto interrupt a latching circuit for a relay of the control circuit 12upon receipt of a carrier in the receiver 17, thereby de-energizing thedeflector solenoid 38 and resetting the station deflector 15. Thedeflector reset contact 50 may be of any suitable construction and may,for example, be a switch which is tripped as the carrier passes throughthe station tube 18. The tripping can be mechanical in nature such asoccurs if the carrier strikes a movable switch-actuating arm projectinginto the carrier path. The switch tripping can also be magnetic innature such as occurs if the carr 1er comprises a magnet which trips areed switch positioned adjacent the carrier path near the station tube18. The control circuit 12 includes a security relay having one terminalconnected in common with the conditloning contact 31 and a latchingcontact 61, and a second termlnal connected to a source of positivepotential 62.

The latching contact 61 is controlled by the security relay 60, closingupon energization of the security relay for completing a portion of alatching circuit for the security relay. The other portion of thelatching circuit for the security relay 60 constitutes a normallyclosed, key-controlled switch 63 connected between ground potential 64and the latching contact 61. The switch 63 may be of any suitable designadapted to be opened upon insertion of a security key K. Theconditioning contact 31 which is normally open, disables the securityswitch if the destination button 14 has not previously been actuated.Thus, the destination switch 14 must be actuated prior to actuation ofthe security switch 20 if carrier transmission in the security mode isdesired. The relay 60 also controls the contacts 37 and 47 for actuatingthe lamp 35 and lock 22 upon ener-gization of the relay 60.

The control circuit 12 further includes the destination relay 27 whichhas one terminal connected in common to the destination button 14 andthe latching contact 52 and another terminal connected to a source ofpositive potential 66. This relay latches through its own contact 52 andthe normally closed reset contact 50, maintaining its other contact 41closed for energizing the solenoid 38 and operating the stationdeflector 15.

In operation, if transmittal of a carrier in the conventional mode isdesired a carrier is inserted into the main tube 16 via the insertionport 13, and the destination switch 14 corresponding to the receivingstation 12 to which the carrier is to be transmitted is depressed. Whenthe destination switch 14 is depressed the movable contact ismomentarily closed completing the energization circuit to thedestination relay 27 via closed contact 25 and line 28. The destinationrelay 27 upon energization closes the latching contact 52 completing thedestination relay latching circuit via the normally closed deflectorreset contact 50 and the latching contact 52. Energization of thedestination relay 27 in response to momentarily depressing thedestination switch 14 also closes the station deflector contact 41completing an energization circuit through the contact 41 of thedeflector solenoid 38, cansing the deflector solenoid to becomeenergized. Energization of the deflector solenoid 38 in turn iseffective to position the deflector mechanism (not shown) of thedeflector station 15 in the main pneumatic tube 16 to thereby'interceptand deflect the carrier which is inserted through the port 13 andtransmitted through the main pneumatic tube to the receiver 17 via thepneumatic station line 18.

Passage of the deflected carrier through line 18 transfers the resetcontact 50 from its normally closed state, momentarily interrupting thelatching circuit for the destination relay 27, thereby producingde-energization of the destination :relay. With the destination relay 27deenergized the latching contact 52 transfers to its normally opencondition preventing re-energization of the destination relay 27 whenthe deflector reset contact 50 returns to its normally closed stateafter passage of the carrier to the receiver 17. Assuming that thesecurity button 20 has not been actuated subsequent to actuation of thedestination switch 14, the electromagnetic receiver lock 22 remainsde-energized, allowing personnel at the receiving station to have accessto the receiver 17 for withdrawing the carrier.

If transmission of a carrier in the security mode is desired, thecarrier is inserted and the appropriate destination switch 14 andsecurity switch 20 are actuated. Actuation of the destination switch 14functions, as described previously with respect to operation of thesystem in the conventional mode, to momentarily close the contact 25,energizing and latching the destination relay 27, and thereby operatingthe deflector mechanism (not shown) of the station deflector 15.Energization of the relay 27 also closes the normally open conditioningcontact 31, enabling the security relay 60 to become energized whencontact 29 is momentarily closed by actuation of the security switch 20.

With the conditioning contact 31 closed and the security switchactuated, an energization circuit is completed to the security relay 60via the closed contacts 29 and 31, energizing the security relay.Energization of the security relay 60 in turn closes latching contact 61completing a latching circuit for the security relay via closed latchingcontact 61 and the normally closed key switch 63. Energization andlatching of the security relay 60 closes the receiver lock contact 47completing an energization circuit to the electromagnetic receiver lock22 actuating the eletromagnetic receiver lock. With the electromagneticlock 22 actuated, the receiver door or closure 73 is locked and accessto the reeciver for removal of the transmitted carrier is preventedexcept to those authorized personnel possessing a security key K.

In addition, with the security relay 60 energized and latched, thesecurity lamp contact 37 is closed completing an energization circuit tothe security lamp 35, thereby providing a visual indication at thetransmitting station 10 of the existence of the security operationalmode. More specifically, the lamp 35 indicates, when illuminated, thatthe electromagnetic lock 22 is energized and the reeciver 17 locked.

The electromagnetic receiver lock 22 remains actuated and the receiver17 locked until the security key is inserted into the key switch 63.When the security key is inserted into the key switch 63 the key switchopens and the latching circuit for the security relay 63 is momentarilyinterrupted, de-energizing the security relay '60. Deenergization of thesecurity relay 60 in turn transfers the latching contact 61 to itsnormally open condition preventing the security relay 60 from becomingagain energized through the normally closed key switch 63 uponwithdrawal of the security key from the key switch. De-energization ofthe security relay 60 also returns contact 37 to its normally open stateextinguishing the security lamps 35, thereby providing a visualindication at the transmitting station that the electromagnetic receiverlock is no longer actuated.

The deflector mechanism (not shown) of the deflector station 15 isreturned to its normal, non-deflecting state in the same manner asdescribed above with respect to the conventional operational mode.Specifically, the station deflector 15 is reset :by de-energization ofthe deflector solenoid 38 in response to opening of contact 41 whichoccurs when the deflector reset contact 50 opens, momentarilyinterrupting the latching circuit and deenergizing the destination relay27 as the carrier passes from the main tube 16 through the station tube18 to the receiver 17.

A second preferred embodiment of a pneumatic carrier conveying systemconstructed in accordance with the principles of this invention isdepicted in FIGURE 2. This system includes a carrier transmittingstation having a tube insertion port 101 into which carriers are placedfor transmission to a receiving station 103 via a main pneumatic tube104. As those skilled in the art will appreciate, this embodiment likethe embodiment of FIG- URE 1, may also contain a plurality oftransmitting and receiving stations 100 and 103, respectively, locatedat diiferent positions throughout the conveying system in accordancewith the needs of the user. The system of FIG- URE 2, like the system ofFIGURE 1, is operable in either a conventional mode or a security mode.

In the conventional mode of operation the carrier is inserted into themain tube 104 via the tube insertion port 101 after having set theappropriate destination number on the carrier, herein termed theconventional destination number, corresponding to the particular one ofthe receiving stations 103 to which it is desired to transmit thecarrier. Having set the conventional destination number on the carrierand inserted it into the main tube 104 the carrier travels through thetube 104 passing the destination number reading stations associated,respectively, with the various receiving stations 103. When the carrierpasses through the destination number read station, herein termed thedesignated read station, associated with the receiving station 103 towhich the carrier is to be transmitted, herein termed the designatedreceiving station, a read signal is generated by the designated readstation which is operative to actuate the station deflector 112 of thedesignated receiving station. The station deflector 112 in response tothe read signal deflects the carrier traveling in the main tube 104 intothe receiver via the station tube 116. When the carrier has arrived inthe receiver 115 it is free to be removed by the personnel at thereceiving station.

If it is desired to operate the system of FIGURE 2 in the security mode,the carrier is inserted into the main tube 104 via the tube insertionport 101 after having set a destination number on the carrier, hereintermed the security destination number, corresponding to the station towhich the carrier is to be transmitted. This security destination numberdiffers from the conventional destination number. Specifically, thesecurity destination numher, when it passes the designated read station110 will, in addition to operating the deflector 112 of the designatedreceiving station for diverting the carrier into the receiver 115, alsooperate an electromagnetic receiver lock of the designated receivingstation, preventing access to the receiver 115 except by authorizedpersonnel possessing a security key. Thus, when the carrier having asecurity destination number is inserted into the main pneumatic tube 194the carrier travels down the tube successively passing the read stationsuntil it reaches the designated read station whereupon suitable signalsare generated by the read station. The signals so generated *actuate thedeflector 112 of the designated receiving station to thereby deflect thecarrier into the receiver 115 via the station tube 116, and actuate theelectromagnetic receiver lock 120 for preventing unauthorized access tothe carrier.

The transmitting station 100, more specifically, includes the tubeinsertion port 101 permitting carriers having destination numberstherein to be inserted into the main tube 104. No additional controls orapparatus is required at the transmitting station 100.

The receiving station 103 includes the station deflector 112 which isprovided with a solenoid for actuating upon energization a deflectormechanism (not shown) of the station deflector 112. The deflectorsolenoid 125 is connected to a grounded terminal 126 via the normallyopen, relay operated station deflector contact 127 which directlycontrols solenoid energization and to a source of positive potential128. A normally closed deflector reset contact 129 is connected betweena grounded terminal 130 and a latching contact 131. The deflector resetcontact 129 is opened in response to the passage of a carrier throughthe station tube 116 to the receiver 115, interrupting a latchingcircuit for a relay which indirectly controls the deflector solenoid 125to be described. The electromagnetic lock 120 forming a portion of thereceiving station 103 is connected between a grounded terminal 132 via areceiver lock contact 133 and a source of positive potential 134. Thereceiving station 103 further includes a normally closed key switch 137connected between a grounded terminal 138 and a latching contact 139.The key switch 137 is adapted to be opened in response to the insertiontherein of the security key K by authorized personnel seeking access toa locked receiver.

The key switch 137, station deflector 112, tube insertion port 101,deflector reset contact 129, receiver115 and electromagnetic receiverlock 120, and tubes 104 and 116 of the embodiment of FIGURE 2 have thesame functions and structure as their respective counterparts in theembodiment of FIGURE 1.

A carrier suitable for use in the embodiment of this invention may be ofthe type constructed in accordance 8 with the principles disclosed inGerhardt Todt, et al., US Patent 3,117,743, for Automatic Pneumatic TubeCarrier, Jan. 14, 1964. With carriers of the type disclosed in theaforementioned patent, two of the plurality of destination numbersprovided on the carrier are allotted for each destination in theconveying system, one of the two destinations corresponds to thesecurity destination number and the other corresponds to theconventional destination number. Thus, with carriers of this type inwhich, for example, it is possible to enter twenty different destinationnumbers, transmission to ten diflerent stations in both the conventionalmode and the security mode is possible.

The read station includes a first contact 140 connected to the groundedterminal 141, a second contact 142 connected to the anodes of diodes 143and 144, and a third contact 145 connected to the junction of thecathode of diode 144, the latching contact 131 and a destination relay147. The destination relay 147 is also connected to a source of positivepotential 148, and functions to control the energization of thedeflector solenoid 125 via the contact 127. The latching path fordestination relay 147 includes contacts 131 and 139. The read stationfurther includes a security relay connected between a source of positivepotential 149 and the junction of the cathode of diode 143 and thelatching contact 139. The security relay 150 latches through its contact139 and the key switch 137 and, via its contact 133, controls theenergization of the electromagnetic receiver lock 120.

The read stations associated with the various receiving stations areeach responsive to different security destination numbers and differentconventional destination numbers. For example, if a carrier passesthrough the read station bearing the conventional destination numbercorresponding to that read station, the contacts 140 and 145 are bridgedactuating the station deflector 112, but not the electromagneticreceiver lock, producing operation in the conventional mode. However, ifthe same carrier passes through the read station bearing the, securitydestination number corresponding to that read station, the contact 140and a contact 142 are bridged actuating both the station deflector 112and the electromagnetic receiver lock 120, producing operation in thesecurity mode.

One form of carrier suitable for use with the embodiment of FIGURE 2 isdepicted in FIGURE 3. The carrier, generally indicated by the referencenumeral 160, includes an open-ended tube 161 having a destinationcontrolling end cap 162 and a security indicating end cap 163. At leastone of the end caps 162 and 163 is selectively removable to permitinsertion of an article in the tube 161 for transmission. The end caps162 and 163 for reasons to become evident hereafter, are alsoselectively rotatable relative to the tube 1611. Tube 161 does notrotate when in the tube 104 by reason of a radially projecting key 159which engages a slot 158 formed in the tube wall 167. The destinationcontrolling end cap 162 and the security indicating end cap 163 includeaxially disposed electrically conductive contact bridging bars 162A and163A, respectively, secured to their respective exterior cap surfaces.Bridging bar 162A, when in the angular position shown, is adapted tomomentarily bridge contacts 140 and 145 as the carrier 160 passesthrough the read station 110. The bridging contact 163A on the securityindicating end cap 163, when in the angular position shown, is adaptedto momentarily bridge contacts 142 and 145 as the carrier 160 passesthrough the read station 110.

Should it be desired to transmit the carrier 160 to a differentreceiving station the angular position of the destination controllingend cap 162 is altered from that shown in FIGURE 3 to position thebridging contact 162A at the appropriate angular position correspondingto the particular angular position of the contacts 140 and 145 of thedestination to which it is desired to transmit the carrier. Likewise,should it be desired to transmit the carrier 160 in a nonsecurity modethe angular position 9 of the security indicating cap 163 is altered toa position diflerent from that shown in FIGURE 3 wherein the bridgingbar 163A does not bridge the contacts 142 and 145 at the read station110 associated with the destination to which it is desired to transmitthe carrier.

In operation, if transmission of a carrier in the conventional mode isdesired, the conventional destination number corresponding to thestation to which the carrier is to be transmitted is set into thecarrier by rotating the destination controlling end cap 162 to aposition such that the bridging bar 162A bridges the contacts 140 and145 at the read station 110 associated with the desired destination.With the conventional destination number so set the carrier is insertedinto the main pneumatic tube 104 at the transmitting station 100 via thetube insertion port 101. Having inserted the carrier into the mainpneumatic tube 104 the carrier travels down the tube successivelypassing the read stations 110 until it arrives at the designated readstation whereupon the contacts 162A on the carrier, the position ofwhich has been adjusted in accordance with the conventional destinationnumber, bridges the contacts 140 and 145 at the read station 110. Thebridging of the contacts 140 and 145 in response to the arrival of thecarrier at the designated read station completes an energization circuitto the destination relay 147 energizing this relay. The energization ofthe destination relay 147 closes the latching contact 131 completing alatching circuit for the destination relay through the normally closeddeflector reset contact 129. The energization and latching of the relay147 closes the station deflector contact 127 completing an energizationcircuit through the station deflector contact to the deflector solenoid125. Completion of this energization circuit energizes the deflectorsolenoid actuating the deflector mechanism (not shown) of the stationdeflector 112. The actuated station deflector 112 is eflective todeflect the transmitted carrier into its associated receiver 115 via thestation tube 116.

Passage of the carrier through the station tube 116 momentarily opensnormally closed deflector reset contact 129, momentarily interruptingthe latching circuit for the destination relay 147. The destinationrelay 147 becomes de-energized transferring the latching contact 131 toits normally open condition, preventing the destination relay 147 frombecoming re-energized upon the closure of the deflector reset contact129 upon passage of the carrier past the contact 129. Thede-energization of the destination relay 147 also transfers the stationcontact 127 to the normally open position, interrupting the energizingcircuit for the deflector solenoid 125 causing it to become de-energizedand the station deflector 112 to be reset or disabled. Since thesecurity relay 150 has not become actuated in response to the generationof a signal by the read station 110 the electromagnetic receiving lock120 remains de-energized and the door or closure of the receiver 115 canbe opened by persons manning the receiving station without use of thesecurity key, thereby providing free access to the carrier.

It operation in the security mode is desired, the security modedestination number is set into the carrier by rotating the securityindicating end cap 163 to the position shown in FIGURE 3 wherein thebridging contact 163A is aligned with the contacts 142 and 145, and thecarrier inserted through the tube insertion port 101 into the mainpneumatic tube 104. Having set in the security designation number andinserted the carrier into the main pneumatic tube 104, the carrierpasses through successive read stations until it arrives at thedesignated read station. When the carrier reaches the designated readstation the contacts 163A on the carrier which have been set inaccordance with the security destination number are effective to bridgethe contact 142 and the grounded contact 140.

The bridging of contacts 140 and 142 is eflective to complete anenergization circuit through the diode 144 causing the destination relay147 to become energized and to latch through its latching contact 131and the normally closed deflector reset contact 129. The energizationand latching of the destination relay 147 is also effective to close thestation deflector contact 127 energizing the deflector solenoid 125 andthereby actuating the station deflector 112. With the station deflector112 actuated, the carrier is deflected to the receiver via the stationtube 116. The passage of the carrier through the station tube 116 opensthe normally closed deflector reset contact 129' momentarilyinterrupting the latching circuit for the destination relay 147 causingthis relay to become de-energized. The de-energization of thedestination relay 147 is effective to de-energize the deflector solenoiddisabling or resetting the station deflector 112. In addition, thelatching contact 131 is returned to its normally open state preventingre-energization of the destination relay 147 by the return of thedeflector reset contact 129 to its normally closed state subsequent tothe passage of the carrier into the receiver 115.

The bridging of the contact and 142, which occurs when the read station110 senses the security destination number, is also eflective tocomplete an energization circuit to the security relay via the diode 143energizing the security relay. The security relay 150 latches throughits latching contact 139 and the normally closed key switch 137 and iseffective to close the normally open receiver lock contact 133,completing an energization circuit to the electromagnetic receiver lock120. With this circuit complete, the electromagnetic receiver lock 120becomes energized preventing access to the receiver 115 by persons otherthan those authorized who possess a security key.

De-actuation of the electromagnetic receiver lock 120 permits access tothe receiver 115 for removing the carrier. De-actuation is accomplishedby inserting the security key K into the key switch 137, momentarilyinterrupting the latching circuit for the security relay 150, in turn,causing the security relay to become de-energized. The de-energizationof the security relay in turn transfers the receiver lock contact 133 toits normally open position interrupting the energization path for theelectromagnetic receiver lock 120. With this energization pathinterrupted the electromagnetic receiver lock 120 becomes de-energized,permitting removal of the carrier from the receiver 115.

As those skilled in the art will appreciate, a variety of modificationsof the foregoing embodiments may be made without departing from thespirit and scope of this invention. For example, the key-operatedsecurity switch may alternatively be a normally closed singlepole-double throw switch, which itself is not key-operated, but which islocated in a secured location. This effectively prevents all personnel,except those authorized to enter the secured location, from operatingthe switch and unlocking the receiver.

Instead of using a security lamp contact 37, which is actuated inresponse to the energization of security relay 60, to complete anenergization circuit to the security lamp 35, it is contemplated that acontact located at the receiver 17 can be used. Such a contact can beadapted to complete an energization circuit to the security lamp 35 inresponse to the actual locking of the electromagnetic receiver lock 22.Thus, instead of the security lamp 35 becoming energized in response tomerely energizing the security relay 60, the lamp 35 becomes energizedwhen the electromagnetic receiver lock 22, in fact, becomes locked. Inthis way, should the electromagnetic receiver lock 22 fail to lock inresponse to the energization of the security relay 60, the lamp 35 doesnot become energized, thereby preventing the lamp 35 from providing afalse indication that the receiver 17 is locked when, in fact, theelectromagnetic receiver lock 22 has not locked.

It is also contemplated that instead of the momentarily operabledestination switch 14 and security switch 29, which operate the stationdeflector 15 and the electromagnetic receiver lock 22, respectively,telephone dials may be provided. With apparatus of this type, iftransmission to a given station is desired in the security mode, a firstnumber is dialed, while if transmission is desired to that station inthe unsecured mode, a second number is dialed. In each case, that is, inboth the secured and unsecured transmission modes, the telephone dial iseffective to energize the appropriate ones of the destination andsecurity relays 27 and 60 for operating the station deflector 15 and theelectromagnetic receiver lock 22, respectively.

It is further contemplated that instead of the set of electricallybridgeable contacts 140, 142 and 145 provided in the read station 110 ofthe preferred embodiment of FIGURE 2, other means of initiating thesecured mode of carrier transmission may be provided. For example, it iscontemplated that a read station 110 operating on magnetic principlesmay be employed. Thus, instead of setting dials on the carrier which areoperative to cause electrical coupling of the contacts 140, 142 and 145when the carrier arrives at the read station 110, the carrier may beprovided with selectively positionable magnets which, when the carrierarrives at the read station 110, operate suitable magnetic reed switchesthereby completing energization circuits to the various relays of thecontrol circuit.

It is further contemplated that instead of dialing one number fortransmitting in the security mode and another number for transmitting inthe unsecured mode, a single destination number can be used for eachstation in conjunction with a selectively positionable security leverprovided on the carrier. Thus, to transmit in the security mode it isnecessary to dial the number corresponding to the desired destination,as well as to actuate the selectively positionable security leverprovided on the carrier. The dialing of the destination number functionsto operate the station deflector of the appropriate station whileactuation of the security lever functions to energize the security relayof that station. When transmission in the unsecured mode is desired, thesecurity lever' is not actuated, the destination number only beingdialed. By using a dialing device in conjunction with a security leverin the manner indicated, if a two digit dialing device is used, 100destinations may be serviced since only one number is required for eachdestination, the security mode being indicated by actuating the securitylever provided on the carrier. In contrast, if a two digit dialingdevice is utilized in a system in which different numbers are providedfor both the secured and unsecured mode of transmission, only 50receiving stations can be serviced.

Finally, it is contemplated that the electromagnetic receiver lock 22may be a pneumatic or hydraulic device which is electromagneticallyactuated. Thus, instead of mechanically coupling the electromagneticdevice 22 to the receiver 17, the electromagnetic device is coupled tothe receiver 22 via either a pneumatic or hydraulic actuator.

Having described my invention, I claim:

1. In a pneumatic tube system of the type in which carriers arepneumatically transported through a tube from a transmitting station toa remotely located receiving station, the combination comprising:

a receiver located at said receiving station in communication with saidpneumatic tube for receiving carriers transported through said tube tosaid receiving station;

a selectively lockable closure associated with said receiver forrestricting access to said receiver for preventing withdrawal of acarrier therefrom when said closure is locked; and

a closure controller associated with said closure including closurelocking means located at said receiving station for locking said closurewhen actuated, means located at said transmitting station for actuatingsaid closure locking means to thereby lock said closure, and meanslocated at said receiving station to deactuate said locking means forunlocking said closure, said deactuating means being unresponsive to thepresence of a carrier at said receiving station.

2. The apparatus of claim 1 wherein said selectively operable closurecontroller includes an electromagnetic device coupled to said closurefor placing said closure in one of a condition of lock and unlock whenenergized, wherein said closure locking means includes a lock switch foroperating said electromagnetic device to place said closure in saidlocked condition, and wherein said closure unlocking means includes anunlock switch for operating said electromagnetic device to place saidclosure in said unlocked condition.

3. In a pneumatic tu'be system of the type in which carriers arepneumatically transported through a tube from a transmitting station toa remotely located receiving station, the combination comprising:

a receiver located at said receiving station in communication with saidpneumatic tube for receiving carriers transported through said tube tosaid receiving station;

a selectively lockable closure associated with said receiver forrestricting access to said receiver for preventing withdrawal of acarrier therefrom when said closure is locked; and closure controllerassociated with said closure including closure locking means located atsaid receiving station for locking said closure, said locking meansincluding an electromagnetic device coupled to said closure for placingsaid closure in one of a condition of lock and unlock when energized,means located at said transmitting station for actuating said closurelocking means to lock said closure, said actuating means including alock switch for operating said electromagnetic device, and means locatedat said receiving station for deactuating said closure locking means forunlocking said closure, said deactuating means being unresponsive to thepresence of a carrier at said receiving station and including an unlockswitch for operating said closure locking means to place said closure insaid unlock condition.

4. The apparatus of claim 3 wherein said closure controller includes asecurity relay adapted to be placed in one condition of energization byactuation of said lock switch and in another condition of energizationby actuation of said unlock switch in response to insertion of saidsecurity 'key into said key-controlled device, said relay having acontact interconnected in the energization circuit of saidelectromagnetic device for operating said device to lock said closurewhen said lock switch is actuated and to unlock said closure when saidunlock switch is actuated.

'5. The apparatus of claim 4 wherein said relay includes a securitycontact and further including a signal device located at saidtransmitting station, said signal device being under the control of saidsecurity contact for providing an indication of the locked and unlockedstatus of said closure.

6. 'In a pneumatic tube system of the type in which carriers arepneumatically transported through a tube from a transmitting station toa remotely located receiving station, the combination comprising:

a receiver located at said receiving station in communication with saidpneumatic tube for receiving carriers transported through said tube tosaid re- 65 ceiving station;

a selectively lockable closure associated with said receiver forrestricting access to said receiver for preventing withdrawal of acarrier therefrom when said closure is locked;

a carrier having a security status indicator means associated therewith,said indicator means being alternatively and selectively operable in asecurity condition and a non-security condition; and

a read station associated with said tube and located be- 7 tween saidtransmitting and receiving stations for detecting the passagetherethrough of a carrier having said indicator in said securitycondition, said read station including a closure controller for lockingsaid closure in response to the detection by said read station of saidcarrier having said indicator in said security condition.

7. The apparatus of claim 6 wherein said closure controller includesselectively operable closure unlocking means located at said receivingstation for unlocking said closure.

8. The apparatus of claim 7 wherein said closure controller includes anelectromagnetic device coupled to said closure for placing said closurein one of a condition of lock and unlock when energized, wherein saidreader includes switch means actuated in response to the passagetherethrough of a carrier residing in said security condition foroperating said electromagnetic device to lock said closure, and whereinsaid unlocking means includes switch means for operating saidelectromagnetic device to unlock said closure.

9. The apparatus of claim 8 wherein said closure unlocking meansincludes a security key and a security keycontrolled device coupled tosaid unlock switch for preventing unauthorized operation of said unlockswitch.

10. The apparatus of claim 9 wherein said reader includes at least twoelectrical contacts adapted to be electrically coupled in response tothe passage therethrough of a carrier residing in said securitycondition, said contacts being in circuit arrangement with saidelectromagnetic device for locking said closure when coupled.

11. The apparatus of claim 10 wherein said closure controller includes asecurity relay adapted to be placed in one condition of energization bysaid coupling of said contacts and in another condition of energizationby actuation of said unlock switch in response to insertion of saidsecurity key into said key-controlled device, said relay having acontact interconnected in the energization circuit of saidelectromagnetic device for operating said device to lock said closurewhen said contacts are coupled and to unlock said closure when saidunlock switch is actuated.

I 12. In a pneumatic tube system of the type in which carriers arepneumatically transported through a tube from a transmitting station toa remotely located receiving station, the combination comprising:

a receiver located at said receiving station in communication with saidpneumatic tube for receiving carriers transported through said tube tosaid receiving station;

a selectively lockable closure associated with said receiver forrestricting access to said receiver for preventing withdrawal of acarrier therefrom when said closure is locked; and

a closure controller associated with said closure including a closurelocking means actuable from said transmitting station for locking saidclosure and a closure unlocking means located at said receiving stationfor unlocking said closure, said unlocking means being unresponsive tothe presence of a carrier at said receiver.

References Cited UNITED STATES PATENTS 5/1920 Botscheider 243-36 9/1956Hanson 24319 US. Cl. X.R.

